Per the sdk-rfc, implement retrieval of server duration and handling of zombie responses.
For server duration, signal via HELO understanding of duration, which should be on by default. Adapt KV parsers to handle new magic and server duration, with decoding. Aggregate and log per spec.
For Zombie Responses, implement handling of zombies, discarding of all but the top 10 trophies in the last ten seconds, and logging per spec.